Apparently, Crucial/Micron has finally overcome the lo-density memory requirement in these PC133 sticks and we are the ultimate winners. I.e., no more searching for expensive lo-density PC100 memory for these systems.

I ordered yesterday a couple units for my T-20... let's hope they will work fine !. BTW, my units come from UK to Spain and price is higher than in USA. But it still is good enough to upgrade my 256Mb T-20!

soon I´ll be owner of a used T20 (2647-84G) , and I´ve planned to upgrade it with the www.crucial.com SDRAM SO-DIMM 2 x 256 Mb which you were talking of in earlier posts and which aparently work fine with older T-models.

My question is if this kind of RAM works fine in every T20 model, or if there are some exceptions.

Also I would like to buy a faster CPU (actually the T20 runs with a 700 Mhz CPU) and a bigger HD.

I would be very thankful if anybody could give me an information what´s the fastest CPU which works fine with the last BIOS and also regarding the HD. If somebody knows also a link where to buy the items for a good price, it would be great.

Hi folks,
I skimmed over this thread but didn't see it mentioned: has anyone mixed this PC133 with another stick of PC100?

My T20 has an IBM certified(not sure on the mfg'r without opening it up) stick of 128M that I don't want to pull out just yet. I'll be replacing the other 64M module with the 256M

Cheers,
Jamie

::edit:: Had I realized that they were now selling their PC133 for PC100 applications, I would have bought two. I used their 'application selector' before coming across the sticky atop this forum. ::edit::

I have a T20 [2647-21G] 650MHz PIII with 128MB PC100 in one slot only. I nipped off to Crucial as per this excellent thread but seem to have more questions than answers. Here they are. Crucial seem only to have PC133 for either 128MB or 256MB.
1. Would 256MB PC133 in the 2nd slot work? or should I bite the bullet and get 2 x 256MB PC133? [which I don't really need as I only use the T20 for the basics - word processing, website stuff, and ActionScript when away from home.]
2. I think the Crucial chips are SDRAM [?] whereas what I have I think is SDR. Same difference? Does it matter?
3. From previous threads 512MB seems to be the max for memory but according to the Crucial scan I have "max 1024MB". I assumed 512 max meant total in both slots or am I missing something? [apart from sufficient brain cells of my own!]
4. Should I update the BIOS before? after? inserting new memory? Current BIOS is IBM 1YET43WW [1.07] 12/12/1999. If I should update, could someone advise where? I have done this on other machines so not a total novice. First time I ended building a new pc [good for the character] and second time I updated without breaking anything. So it's Technology 1: Me 1. Time for the decider?
Thanks for any advice. Duncan

1. Would 256MB PC133 in the 2nd slot work? or should I bite the bullet and get 2 x 256MB PC133?

Generally, you should not mix different speed modules. Some systems are able to figure out what you have installed and adjust itself to the slowest one. However in this case, I do not believe this is true for the T20. I think the system is locked into using a specific timing. What is important when using PC133 modules is that you use ones marked CL2 and not CL3. This has to do with what is called the "CAS Latency" of the memory access. Lower numbers are faster parts. Your current PC100 module should be CL2. Whatever else you install should also be CL2. As to the amount of memory, I would say the more the better. Depending upon the operating system you are running and the number of processes executing in the background, 384MB may not be enough. I know for some demanding programs, 512MB is a minimum amount. Your call.

Edit Jan '08: Note, please disregard my comments about sticking with CL2. The T21 and T22 systems can use CL3. I'm assuming that with the same chipset, that the T20 would as well. Ray

duncan wrote:

2. I think the Crucial chips are SDRAM [?] whereas what I have I think is SDR. Same difference? Does it matter?

Only the T23 can use 1GB of RAM, the earlier T models are limited to 512MB.

James is correct and I need to check my facts a little better next time. T20-22 systems use Intel 440BX chipset which is limited to 512MB. The T23s use the 830MP chipset which allows 1024MB. Sorry for the error (as Ray goes and hides...).

edit: I just used my T21 and ran the system check that Crucial provides. It said that it could not identify my system but that it had 128MB in it (correct), that slot 1 was used (correct) and that it supports 1024MB (not correct). Did the same with my T23 that has 1024MB installed. It reported that it saw all 1024MB but that the system (it thought it was looking at a T22) has a maximum limit of 512MB. In short, don't trust the Crucial memory tool to tell you what you have/need. Go through the drop-down selections to find your system and that should tell you the memory requirements.

Many thanks again Ray for an excellent post! Forget the sackcloth and ashes routine! [Thanks James for the added info and for the original post about Crucial.] I shall scamper off and update the BIOS and lash out on 2 x 256 provided they are CL2. Thanks again to all. Duncan

James is correct and I need to check my facts a little better next time. T20-22 systems use Intel 440BX chipset which is limited to 512MB. The T23s use the 830MP chipset which allows 1024MB. Sorry for the error (as Ray goes and hides...).

Don't go too far Ray!

I made exactly the same mistake myself yesterday. TWICE!

Regards,

James

_________________James at thinkpads dot com

5.5K+ posts and all I've got to show for it are some feathers.... AND a Bird wearing a Crown

The T20 was the single most reliable laptop I've ever owned, and in the last 20 years I've owned many. It is true that you can buy a brand-new laptop for about $400 and with that reality, putting $150 into T20 memory upgrades (to the low maximum of 512MB) might not seem such a great deal. The reality, however, is that your 512MB T20 is a MUCH better laptop than any of the cheap consumer-grade junk currently for sale.

_________________"An atheist is just somebody who feels about Yahweh the way any decent Christian feels about Thor or Baal or the golden calf. As has been said before, we are all atheists about most of the gods that humanity has ever believed in. Some of us just go one god further."

Just wanted to pass on to any interested party that there is an eBay seller who has 25 pieces of FRU#33L3070 for $34.99 each (I bought two) 256mb SDRAM PC100 CL2 - pulled from working laptops and 30 day return policy. Seller name is worldrecycler.